Flow distributor for heat transfer plate

ABSTRACT

A flow distributor for a heat transfer device having a plurality of channels includes a sheath defining a plurality of distributor holes, each distributor hole configured to be in fluid communication with a respective channel inlet of each channel of the heat transfer device and an insert defining a plurality of fluid channels therein and a fluid inlet, each fluid channel in fluid communication with the fluid inlet. The insert is disposed within the sheath to seal the fluid channels with each fluid channel in fluid communication with a respective one of the distribution holes. The fluid inlet includes an inner inlet and an outer inlet radially outward from the inner inlet for mixing a fluid flow in the fluid inlet for evenly distributing fluid flow (e.g., a two phase flow) into the fluid channels of the insert and into each channel of the heat transfer device.

BACKGROUND

1. Field

The present disclosure relates to heat transfer systems, and moreparticularly to heat transferring structures and plates.

2. Description of Related Art

Electrical components in circuitry (e.g., aircraft or spacecraftcircuits) require sufficient heat transfer away from the componentsand/or the system in order to continue to function. Many mechanisms havebeen used to accomplish such a task, e.g., fans, heat transfer plates,actively cooled devices such as tubes or plates including tubes thereinfor passing coolant over a hot surface. While circuitry continues toshrink in size, developing heat transfer devices sufficient to move heataway from the components is becoming increasingly difficult.

Certain heat transfer devices include multiple layers of passages forrefrigerant to pass therethrough, all connected to a single inlet. Dueto co-existence of multiple states (e.g., liquid and gas) of therefrigerant, the fluid enters into the different layers unevenly,causing uneven thermal distribution and thermal acceptance of eachlayer. This has presented a limitation on heat transfer that hastraditionally had to be taken into account in designing for satisfactorythermal performance.

Such conventional methods and systems have generally been consideredsatisfactory for their intended purpose. However, there is still a needin the art for improved heat transfer devices. The present disclosureprovides a solution for this need.

SUMMARY

In at least one aspect of this disclosure, a flow distributor for a heattransfer device having a plurality of channels includes a sheathdefining a plurality of distributor holes, each distributor holeconfigured to be in fluid communication with a respective channel inletof each channel of the heat transfer device and an insert defining aplurality of fluid channels therein and a fluid inlet, each fluidchannel in fluid communication with the fluid inlet. The insert isdisposed within the sheath to seal the fluid channels with each fluidchannel in fluid communication with a respective one of the distributionholes. The fluid inlet includes an inner inlet and an outer inletradially outward from the inner inlet for mixing a fluid flow (e.g., atwo-phase flow) in the fluid inlet for evenly distributing the two phaseflow into the fluid channels of the insert and into each channel of theheat transfer device.

The sheath and the insert can be integral with one another. The channelscan be machined channels between the fluid inlet and the distributorholes. In some embodiments, the insert can be interference fit (e.g.,friction fit) into the sheath. It is also contemplated that the insertand the sheath can be manufactured as a single piece formed togetherusing additive manufacturing or any other suitable method (e.g., lostwax casting).

The channels can be fluidly isolated from each other. The fluid channelscan also be spaced apart circumferentially to balance the pressure droptherein. In certain embodiments, each fluid channel can be defined tohave equal total length from the fluid inlet to the distributor holes.

The outer inlet can include radial ports that allow flow to join withthe inner inlet at an inlet divider, the inlet further defining a fluidchannel port for each fluid channel in the insert to allow for the fluidto flow from the inlet around the divider and into each fluid channel.

The inlet can further define a throat, wherein the inner inlet and theouter inlet meet at the throat such that the throat allows flow from theouter inlet and the inner inlet to converge and mix above the divider.The outer inlet can define a plurality of radial ports leading to thethroat and each outer inlet hole can align with each of the channels ofthe insert.

In another aspect of this disclosure, a method for flowing coolant intoa heat transfer device includes the steps of forming a flow distributorfor a heat transfer device having a plurality of channels, the flowdistributor device comprising a body defining a plurality of distributorholes, each distributor hole configured to be in fluid communicationwith a respective channel inlet of each channel of the heat transferdevice, wherein the body defines a plurality of fluid channels thereinand a fluid inlet, each fluid channel in fluid communication with thefluid inlet, wherein each fluid channel is in fluid communication with arespective one of the distribution holes, wherein the fluid inletincludes an inner inlet and an outer inlet radially outward from theinner inlet for mixing a two phase flow in the fluid inlet for evenlydistributing the two phase flow into the fluid channels defined in thebody and into each channel of the heat transfer device. Forming can bedone in any suitable manner including additive manufacturing or anyother suitable method (e.g., lost wax casting).

In an aspect of this disclosure, a flow director for fluid includes acylindrical flow body extending along a body axis, the body havinginternal and external body walls, and a plurality of outlets along theaxis extending radially through said walls, a cylindrical sheath coaxialwith the flow body, the sheath having a sheath body defined by internaland external sheath walls and a plurality of passages extending axiallyalong the external wall, wherein the external sheath wall is adjacentthe internal flow body wall, and each passage in the sheath wall is influid communication with a respective outlet in the flow body wall, anda flow director inlet configured to deliver fluid to each passage in thesheath wall. The sheath wall can include a first and second passage, andthe axial length of the first passage is greater than the axial lengthof the second passage.

These and other features of the systems and methods of the subjectdisclosure will become more readily apparent to those skilled in the artfrom the following detailed description taken in conjunction with thedrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

So that those skilled in the art to which the subject disclosureappertains will readily understand how to make and use the devices andmethods of the subject disclosure without undue experimentation,embodiments thereof will be described in detail herein below withreference to certain figures, wherein:

FIG. 1A is a perspective view of an embodiment of a flow distributor inaccordance with this disclosure;

FIG. 1B is a cross-sectional view of the flow distributor of FIG. 1A;

FIG. 2 is a cross-sectional view of the flow distributor of FIG. 1A,shown disposed in a multichannel heat transfer device;

FIG. 3 is a rear perspective exploded view of the flow distributor ofFIG. 1A, showing the channel structure on the insert;

FIG. 4 is a front perspective exploded view of the flow distributor ofFIG. 1A, showing the channel structure on the insert and the distributorholes on the sheath;

FIG. 5 is a perspective view of the inlet portion of the flowdistributor of FIG. 1A, showing an embodiment of the outer inlet;

FIG. 6 is a perspective view of the inlet of FIG. 5, showing the innerinlet;

FIG. 7 is a perspective exploded view of a portion of the flowdistributor of FIG. 1A, showing a channel fluidly communicating with theinlet;

FIG. 8 is a cross-sectional perspective view of the flow distributor ofFIG. 1A, schematically showing operation with a two-phase flow with theliquid traveling radially inward through the outer inlets; and

FIG. 9 is a cross-sectional perspective view of the flow distributor ofFIG. 1A, schematically showing operation with a two-phase flow with theliquid traveling axially through the inner inlet.

DETAILED DESCRIPTION

Reference will now be made to the drawings wherein like referencenumerals identify similar structural features or aspects of the subjectdisclosure. For purposes of explanation and illustration, and notlimitation, a perspective view of an embodiment of the flow distributorin accordance with the disclosure is shown in FIGS. 1A and 1B and isdesignated generally by reference character 100. Other views of the flowdistributor of FIGS. 1A and 1B, and aspects thereof, are shown in FIGS.2-9. The systems and methods described herein can be used to evenlydistribute multiphase fluid flow to a heat transfer device havingmultiple channels.

Referring generally to FIGS. 1A, 1B, and 2, a flow distributor 100 for aheat transfer device (e.g., device 201 shown in FIG. 2) includes asheath 101 defining a plurality of distributor holes 107. As shown inFIG. 2, each distributor hole 107 is configured to be in fluidcommunication with a respective channel inlet 204 of each channel 205 ofthe heat transfer device 201.

The flow distributor 100 includes an insert 103 defining a plurality offluid channels 109 therein and a fluid inlet 105. Each fluid channel 109is in fluid communication with the fluid inlet 105. Referringadditionally to FIGS. 3-7, the insert 103 is disposed within the sheath101, and in combination with the inner surface of the sheath 101 (asdiscussed in more detail below) to seal the fluid channels 109 from oneanother within sheath 101, with each fluid channel 109 in fluidcommunication with a respective one of the distribution holes 107.

As also shown in FIG. 5, the fluid inlet 105 includes an inner inlet 105a and an outer inlet 105 b which is radially outward from the innerinlet 105 a. This allows a two-phase flow (as described in more detail,below) to be mixed in the fluid inlet 105 for evenly distributing thetwo phase flow into the fluid channels 109 and, thereby providing eachchannel 205 of the heat transfer device 201 with a mixed two-phase flow.The inlet 105 can include a smaller outer diameter than the portion ofthe insert defining the channels 109 of the insert 103 such that flowcan travel around the inlet 105 to the outer inlet 105 b when the insert103 is inserted into sheath 101 and placed within a heat transfer device201. Any other suitable design to allow fluid to flow to the outer inlet105 b is contemplated herein, e.g., channels defined through an outerportion of the inlet 105).

In some embodiments, the sheath 101 and the insert 103 can be integralwith one another such that they are fused together and/or formed as onepiece in any suitable manner. In other embodiments, the channels 109 canbe machined channels between the fluid inlet 105 and the distributorholes 107.

In some embodiments, the insert 103 is interference fit (e.g., frictionfit) into the sheath 101. Any other suitable fit or attachment iscontemplated herein such that the sheath 101 and insert 103 areconstructed and arranged to insure all of the fluid flows into the holes107, and that there are no fluid leaks between the insert 103 and thesheath 101.

Referring to FIGS. 3 and 4, the channels 109 can be fluidly isolatedfrom each other such that each channel 109 does not mix with otherchannels 109 along the length of the channel 109. The fluid channels 109can also be spaced apart circumferentially and/or otherwise dimensionedto balance the pressure drop therein such that each channel 109experiences a predetermined pressure drop relative to the other channels109 (e.g., the same across all channels 109). In some embodiments, eachfluid channel can be defined to have equal total length and/or volumefrom the fluid inlet 105 to the distributor holes 107 to cause thepressure drop across each channel 109 to be equal. Alternatively, thefluid channels 109 can be unevenly spaced and/or differently sized toachieve a non-uniform pressure drop from hole to hole and/or non-equalflow of fluid out of each hole 107. For example, the channels 109 can beconstructed and arranged such that a greater volume of fluid flowsthrough one or more holes 107 as compared to the fluid flow throughother holes 107.

With reference to FIG. 5, the outer inlet 105 b includes radial ports106 that allow flow to join with flow in the inner inlet 105 a at aninlet divider 111 (e.g, as shown in FIG. 6) such that flow that entersthe inlet 105 is divided into different channels 109 evenly. Unevendivision of the fluid flow is also contemplated herein.

As shown, the outer inlet 105 b can, in some embodiments, define anannulus manifold or any other shape. Referring to FIG. 7, the insert 103can further define a fluid channel port 113 for each fluid channel 109in the insert to allow for the fluid to flow from the inlet 105 aroundthe divider 111 and into each fluid channel 109. The fluid port 113 canbe the upper portion of the fluid channel 109 defined in the insert 103that communicates with inlet 105 at the divider 111, or can include anyother suitable design, such that fluid can flow through the inlet 105(e.g., inner inlet 105 a and/or radial ports 105 b) in into each channel107.

The inlet 105 can further define a throat 110 including a reducingportion. The inner inlet 105 a and the outer inlet 105 b can meet at thethroat 110 such that the throat 110 allows flow from the outer inlet 105b and the inner inlet 105 a to converge and mix above the divider 111.The outer inlet 105 b can define a plurality of radial ports 106 leadingto the throat 110. In some embodiments, each radial port 106 can alignwith a channel port 113 of the insert 103. While it is shown that thereis a single outer inlet hole for each channel port 113, any suitablenumber of radial ports 106 and positioning thereof is contemplated.

It is also contemplated that the insert 103 and the sheath 101 can bemanufactured as a single piece formed together any suitable method suchthat there is no distinct sheath 101 or insert 103, but the same orsimilar channels 109 are defined within the distributor device 100.Suitable methods include, but are not limited to, additive manufacturingand/or lost wax casting. Also, while the flow distributor 100 is shownas being two pieces, it can be fabricated of any suitable number ofpieces.

In another aspect of this disclosure, a method includes forming a flowdistributor 100 for a heat transfer device 201 having a plurality ofchannels. In some embodiments, the flow distributor device is formed asa single piece including a body defining a plurality of distributorholes 107, a plurality of fluid channels 109, and an inlet 105 asdescribed above. Forming can be done in any suitable manner including,e.g., additive manufacturing, lost wax casting.

Referring again to FIG. 2, the flow distributor 100 can be inserted intoa heat transfer device 201 such that the distributor holes 109 are influid communication with the heat transfer channel inlets 204 of eachchannel 205 of the heat transfer device 201. A nozzle 207 can beattached to the inlet 105 of the flow distributor 100 allowing coolantto pass therethrough.

As shown in FIG. 8, a fluid flow within a heat transfer system cantransition to a two-phase flow including a liquid phase flowing along aradially outward portion of the nozzle 207 and a gas phase flowinginside that liquid phase. In such a case, the liquid phase will flowaround the inlet 105 and into the outer inlet 105 b to pass into theinlet 105 while the gas phase flows into the inner inlet 105 a and mixeswith the liquid phase within the inlet. This causes a roughly equalamount of each gas phase and liquid phase into each channel 109, outeach hole 107, through its respective channel inlet 204 and thus intothe heat transfer device 201. Due to the evenly distributed phasespassing through each inlet 204, heat transfer is evened out in the heattransfer device 201 since each heat transfer channel 205 includes asimilarly dense volume of cooling flow.

As shown in FIG. 9, a fluid flow within a heat transfer system cantransition to a two-phase flow including a gas phase flowing along aradially outward portion of the nozzle 207 and a liquid phase flowingradially inward of the gas phase. In such a case, the gas phase willflow around the inlet 105 and into the outer inlet 105 b to pass intothe inlet 105 while the liquid phase flows into the inner inlet 105 aand mixes with the gas phase within the inlet 105. This causes a roughlyequal amount of gas phase and liquid phase into each channel 109, outeach hole 107, through its respective channel inlet 204 and into theheat transfer device 201. Due to the evenly distributed phases passingthrough each inlet 204, heat transfer is evened out in the heat transferdevice 201 since each heat transfer channel 205 includes a similarlydense volume of cooling flow.

The methods and systems of the present disclosure, as described aboveand shown in the drawings, provide for a flow distribution device withsuperior properties including distributing multiple phase flow evenly,e.g., for a multichannel heat transfer device. While the apparatus andmethods of the subject disclosure have been shown and described withreference to embodiments, those skilled in the art will readilyappreciate that changes and/or modifications may be made thereto withoutdeparting from the spirit and scope of the subject disclosure.

What is claimed is:
 1. A flow distributor for a heat transfer devicehaving a plurality of channels, comprising: a sheath defining aplurality of distributor holes, each distributor hole configured to bein fluid communication with a respective channel inlet of each channelof the heat transfer device; and an insert defining a plurality of fluidchannels therein and a fluid inlet, each fluid channel in fluidcommunication with the fluid inlet, wherein the insert is disposedwithin the sheath to seal the fluid channels, wherein each fluid channelis in fluid communication with a respective one of the distributionholes, wherein the fluid inlet includes an inner inlet and an outerinlet radially outward from the inner inlet for mixing a flow in thefluid inlet for evenly distributing the two phase flow into the fluidchannels of the insert and into each channel of the heat transferdevice.
 2. The distributor of claim 1, wherein the sheath and the insertare integral.
 3. The distributor of claim 1, wherein the channels aremachined channels between the fluid inlet and the distributor holes. 4.The distributor of claim 1, wherein the insert is interference fit intothe sheath.
 5. The distributor of claim 1, wherein the channels arefluidly isolated from each other.
 6. The distributor of claim 1, whereinthe fluid channels are spaced apart circumferentially to balance thepressure drop therein.
 7. The distributor of claim 1, wherein each fluidchannel is defined to have equal pressure drop from the fluid inlet tothe distributor holes.
 8. The distributor of claim 1, wherein the outerinlet include radial ports that allow flow to join with the inner inletat an inlet divider, the inlet further defining a fluid channel port foreach fluid channel in the insert to allow for the fluid to flow from theinlet around the divider and into each fluid channel.
 9. The distributorof claim 1, wherein the insert and the sheath are a single piece formedtogether using additive manufacturing.
 10. The distributor of claim 8,wherein the inlet defines a throat, wherein the inner inlet and theouter inlet meet at the throat, wherein the throat allows flow from theouter inlet and the inner inlet to converge and mix above the divider.11. The distributor of claim 10, wherein the outer inlet defines aplurality of radial ports leading to the throat.
 12. The distributor ofclaim 11, wherein the each outer inlet hole aligns with each of thechannels of the insert.
 13. A method for flowing coolant into a heattransfer device, comprising the steps of: forming a flow distributor fora heat transfer device having a plurality of channels, the flowdistributor device comprising: a body defining a plurality ofdistributor holes, each distributor hole configured to be in fluidcommunication with a respective channel inlet of each channel of theheat transfer device, wherein the body defines a plurality of fluidchannels therein and a fluid inlet, each fluid channel in fluidcommunication with the fluid inlet, wherein each fluid channel is influid communication with a respective one of the distribution holes,wherein the fluid inlet includes an inner inlet and an outer inletradially outward from the inner inlet for mixing a two phase flow in thefluid inlet for evenly distributing the two phase flow into the fluidchannels defined in the body and into each channel of the heat transferdevice.
 14. The method of claim 13, wherein forming includes additivemanufacturing.
 15. A flow director for fluid, comprising: a cylindricalflow body extending along a body axis, the body having internal andexternal body walls, and a plurality of outlets along the axis extendingradially through said walls; a cylindrical sheath coaxial with the flowbody, the sheath having a sheath body defined by internal and externalsheath walls and a plurality of passages extending axially along theexternal wall, wherein the external sheath wall is adjacent the internalflow body wall, and each passage in the sheath wall is in fluidcommunication with a respective outlet in the flow body wall; and a flowdirector inlet configured to deliver fluid to each passage in the sheathwall.
 16. The flow director of claim 15, wherein the sheath wallincludes a first and second passage, and the axial length of the firstpassage is greater than the axial length of the second passage.